Reliability of Objectively Measured Sedentary Time and Physical Activity in Adults

摘要: Background In adults, a minimum of 3–5 days accelerometer monitoring is usually considered appropriate to obtain reliable estimates physical activity (PA). However, longer period measurement might be needed sedentary behavior (SED). The aim this study was determine the reliability objectively assessed SED and PA in adults. Methods Eighty-seven adult subjects (28 men; mean (standard deviation) age 31.3 (12.2) years; body mass index 23.7 (3.1) kg/m2) wore GT3X+ for 21 subsequent days, which different wear time criteria (8 12 h/day 3 5 d/week) explored. Variance partitioning along with Spearman-Brown prophecy formula used as basis determining intraclass-correlation coefficients (ICC) number (N) achieve an ICC = 0.80. Week-by-week reported using ICC, Bland-Altman plots absolute measures agreement. Results Seven-10 reliably assess overall- (axis 1 vector magnitude (VM) counts per minute (CPM)) moderate-to-vigorous (MVPA), 3–4 light (LPA), whereas depended on whether adjustments were made (6–8 days) or not (13–15 days). week-by-week ≥0.70 all variables, limits agreement being ±267.8 cpm CPM, ±352.3 VM ±76.8 min/day SED, ±57.8 LPA ±43.8 MVPA, equal 1.0–1.6 standard deviations, when adjustment time. Conclusions For most more than one week Correcting crucial SED. Considerable variability found variables. Researchers need aware substantial intra-individual accelerometer-measurements.